Tone reproduction curve (TRC) target adjustment strategy for actuator set points and color regulation performance trade off

Abstract

A method of controlling an actuator includes determining a function of an actuator value based on a cost function index that represents a relationship between a tone reproduction curve error and the actuator value necessary to achieve a tone reproduction curve target, determining an actual tone reproduction curve error from an obtained sample of a tone reproduction curve and controlling the actuator based on the function and actual tone reproduction curve error to move to a point that represents the tone reproduction curve target. A Xerographic system includes an actuator, an input device that inputs the cost function index and a controller that controls the Xerographic system to obtain the sample, determine an actual tone reproduction curve error from the sample, and control the actuator based on the cost function index and the actual tone reproduction curve error to move to a point that represents the tone reproduction curve target.

1. A method of controlling an actuator for a printing system, comprising:
 determining a function of an actuator value based on a cost function index that represents a relationship between a tone reproduction curve error and the actuator value necessary to achieve a tone reproduction curve target; 
 obtaining a sample of a tone reproduction curve; 
 determining an actual tone reproduction curve error from the obtained sample; and 
 controlling the actuator based on the function and actual tone reproduction curve error to move to a point that represents the tone reproduction curve target. 
 
   
   
     2. The method of  claim 1 , comprising the tone reproduction curve error being a tone reproduction curve steady state error, and the cost function index being a tradeoff between a noise level and actuator value and defining an acceptable noise level at which the printing system can operate. 
   
   
     3. The method of  claim 2 , comprising the actuator value being a position of the actuator, and controlling the actuator to move to a plurality of points that represent a plurality of tone reproduction curve targets. 
   
   
     4. The method of  claim 3 , comprising controlling the actuator to move to the plurality of points until the actuator approaches an upper or lower physical limit of the actuator, and then adjusting the actuator to rapidly move toward an outermost limit of tone reproduction curve errors while maintaining the upper or lower physical limit of the actuator. 
   
   
     5. The method of  claim 1 , comprising determining a predetermined actuator value range within the upper and lower physical limits of the actuator, controlling the actuator to move to a plurality of points, and then move towards an outermost limit of tone reproduction curve errors after the actuator reaches a limit of the predetermined actuator value range. 
   
   
     6. The method of  claim 1 , comprising determining two different tone reproduction curve targets based on preset color calibrations for the printing system. 
   
   
     7. The method of  claim 6 , comprising controlling the actuator to move along a track defined by a plurality of points by switching the actuator between the two different tone reproduction curve targets depending on the actuator value. 
   
   
     8. The method of  claim 1 , wherein the tone reproduction curve error combines all mechanical variation, material variation, and environmental variation into a single variable aligned with an actuator response necessary to maintain the tone reproduction curve target. 
   
   
     9. The method of  claim 1 , comprising controlling the actuator using hysteresis to avoid instability in the actuator. 
   
   
     10. The method of  claim 1 , comprising the method of controlling the actuator being used on a Xerographic system to print an image on a receiving medium using a charge retentive surface. 
   
   
     11. A Xerographic system, comprising:
 an actuator; 
 an input device that inputs a cost function index that represents a relationship between a tone reproduction curve error and an actuator value necessary to achieve a tone reproduction curve target; and 
 a controller that controls the Xerographic system to obtain a sample of a tone reproduction curve, determine an actual tone reproduction curve error from the obtained sample, and control the actuator based on the cost function index and the actual tone reproduction curve error to move to a point that represents the tone reproduction curve target. 
 
   
   
     12. The Xerographic system of  claim 11 , comprising the tone reproduction curve error being a tone reproduction curve steady state error, and the cost function index being a tradeoff between a noise level and the actuator value and defining an acceptable noise level at which the printing system can operate. 
   
   
     13. The Xerographic system of  claim 11 , comprising the actuator value being a position of the actuator, and the controller controlling the actuator to move to a plurality of points that represent a plurality of tone reproduction curve targets. 
   
   
     14. The Xerographic system of  claim 11 , comprising the controller controlling the actuator to move to the plurality of points until the actuator approaches an upper or lower physical limit of the actuator, and then adjusting the actuator to rapidly move toward an outermost limit of tone reproduction curve errors while maintaining the upper or lower physical limit of the actuator. 
   
   
     15. The Xerographic system of  claim 11 , comprising the controller determining a predetermined actuator value range within the upper and lower physical limits of the actuator, controlling the actuator to move to a plurality of points, and then to move towards an outermost limit of tone reproduction curve errors after the actuator reaches a limit of the predetermined actuator value range. 
   
   
     16. The Xerographic system of  claim 11 , comprising the controller determining two different tone reproduction curve targets based on preset color calibrations for the printing system. 
   
   
     17. The Xerographic system of  claim 16 , comprising the controller controlling the actuator to move along a track defined by a plurality of points by switching the actuator between the two different tone reproduction curve targets depending on the actuator value. 
   
   
     18. The Xerographic system of  claim 11 , wherein the tone reproduction curve error combines all mechanical variation, material variation, and environmental variation into a single variable aligned with an actuator response necessary to maintain the tone reproduction curve target. 
   
   
     19. The Xerographic system of  claim 11 , comprising the controller controlling the actuator using hysteresis to avoid instability in the actuator. 
   
   
     20. The Xerographic system of  claim 11 , wherein the Xerographic system is used to print an image on a receiving medium using a charge retentive surface.